Solution for the preparation of rayon



v satisfactory.

and sugars.

Patented June 13, 1944 UNH'ED STATES .RATENT QFFWE SOLUTION FOR m PREPARATION OF BAYON Kenneth B. Brown, West on Pa.-, assignor to Atlas Powder Company; W corporation of Delaware V 11, Del., a

No Drawing. Application July 10, 1942, Serial No. 450,489

7 Claims.

described, it comprises dissolving cellulosic material. usually cotton linters, in a solution of copper tetrammonio-hydroxide and/or carbonate to produce what is commonly called bluesolution. Blue solution isthen extruded through a spinnerette. usually in the form of an orifice plate,

into a bathin which the blue solution gels and sets into a filament and from which it is drawn and collected, usually on reels or in centrifugal baskets. Setting baths may be of a number of different compositions'depending on the type of rayon desired. Hot water and alkali baths have been found quite efiective.

are to be preferred. It is to be noted that a given polyhydric compound may be combined with any number of alkylene oxide groups, for alkylene I oxides may condense with hydroxyl groups of Blue solutions to which this application is particularly directed have been prepared in a number of ways. One manner has been bvweoipitating a complex basic copper sulfate from a copper sulfate solution by means of caustic soda or soda ash, washing the precipitate, then trituratunstable, particularly when warm, and tandem-- pose and turn brown- A number of agentshave been added to blue solutions to stabilize them. A few such agents are sucrose, tartaric acid, and starch. These have not. however, been entirely It is anobject of this invention to provide blue solutions of improved stability.

It has been discovered that blue solutions are 1 groups. As exemplary of such compounds may be mentioned condensation products of alkylene oxides with ethylene glycol, 'glycerine, hexitols, Sugars may be monosaccharides such as pentoses or hexoses, as for example glu- F cose, or higher saccharides, for example, sucrose.

polyhydric compounds, or on hydroxyl groups of hydroxy alkylene'ethersthereof. The hydroxy alkylene ethers of polyhydric compounds of this invention need not be prepared by condensation of the alkylene oxide with the polyhydric compound, but may be prepared in any convenient manner. Condensation: reactions are usually quite conveniently performed, however. Preierred examples of stabilizing compounds of the present invention are hydroxy ethylene, hydroxy propylene, or mixed hydroxy ethylene-propylene ethers of sorbital containing from 6 to 12 ethylene or propylene groups.

The stabilizer may be added during the preparation oi the blue solution or after it has been prepared. Usually it is-added-with the cellulosic constituent. 1

.What is claimed is:'

1. A cuprammonium soiutionof cellulose-for use in the manufacture 'of rayon containing a stabilizing agent which comprises a water soluble hydroxyalkylene ether of a polyhydric compound. said poly vdric compound containing-at least 2 hydroxyl groups.

2. A cuprammonium solution of cellulose according to claim 1 in which-the stabilizing agent is a water soluble hydroxy alkylene ether of a hexitol. I 3. A cuprammonium solution of cellulose according to claim 1 in which the stabilizingv agent is a water soluble hydroxy alkylene ether of a sugar.

4. A cuprammonium solution of cellulose according to claim 1 in which the stabilizing agent is a water soluble hydroxy alkylene ether of a 'p yhydric alcohol.

6. A cuprammonium solution of cellulose according to claim 1 in which thestabilizing agent is a water soluble hydroxy propylene ether of a p lyhydric com ound.

7. A cuprammonium solution of cellulose according to claim 1 in'which the stabilizing agent is a water soluble hydroxy ethylene ether of a polyhydric compound.

assume a. snow. 

